is where a plant's stems increase in thickness, while is where a plant's tips and shoots grow.
is a plant's tendency to grow toward a light source, while
is a plant's response to touch, and
5.
is a plant's response to the force of gravity.
Review Key Questions
Provide evidence and details to support your answers.
6. What are the principal organs of plants and what three types of tissue do they contain?
Organs.

answers are:

lysogenic     viral dna merges with host cell dna

lysogenic     no symptoms

lytic               viral dna takes over

lysogenic     virus does not destroy host cell

lytic               virus destroys host cell

lytic               induces symptoms of viral infection

lysogenic       cell reproduces and spreads provirus

. the sierra madre fault zone of southern california

. the san andreas fault california

the oldest known insects are believed to live around 400 millions ago as suggested by the fossil records.   some plants having woody stems also evolved during this time.

after the evolution of insects the first four legged species or the tetrapods evolved in shallow freshwater habitats from the intermediate species approximately 397 million years ago. the tetrapods went on conquering the land giving rise to amphibians, reptiles, mammals and birds.

the major split in tetrapods first occurred 340 million years ago branching off from amphibians.

363 million years ago when the carboniferous period began the insects started roaming on land and taking flights, following which the four limbed tetrapods adapted in the terrestrial habitat.